Iscarsah newsletter 1 Layout 1 - ICOMOS Open Archive ...openarchive.icomos.org/1582/1/Iscarsah_newsletter_1.pdf · Alessandro Baratta, Earthquake prediction and seismic prevention

IscarsahInternational Scientific Committee on the Analysis andRestoration of Structures of Architectural Heritage

Message of the President ofISCARSAH Stephen Kelley

ear ISCARSAH Colleagues andFriends,

We would like to welcome you to the firstissue of the ISCARSAH Newsletter editedby Vice President Maya Segarra Lagunes!ISCARSAH is a world-wide Committee, andtherefore, we do not know each other asmuch as we would like. This newsletterwill provide us with a forum besides meet-ings and the listserv to share with eachother what we are working on. As you cansee we have adopted a multi-lingual formatfor the newsletter. With Google Translatethese stories from our colleagues can be-come an open book for you.ISCARSAH has grown significantly since2008 and the committee is a strong pres-ence within ICOMOS. Our last meetingduring the General Assembly in Paris hadan unprecedented attendance of 38 per-sons. Such a large committee meeting isdifficult to manage efficiently, but wewere also afforded the opportunity tostrengthen our personal ties. We hadrepresentation from five continents. Forthe first time we held a two hour long we-bcast thus including members from NorthAmerica, Europe, and Asia who were notable to journey to Paris.While in Paris ISCARSAH was fortunate be-come involved with preservation advocacysurrounding the Halle Freyssinet. Followingare excerpts from the Resolution that wasput forward during the General Assembly: Eugène Freyssinet (1879 - 1962) was an in-

novative engineer who was a pioneer in prestressed and post-tensioned concrete structures in the early part of the 20th Century. ICOMOSscientific committees for 20th Century Heritage and Structural Architectural Heritage note that it is important to celebrate the work of LaHalle Freyssinet as a unique and significant concrete building structure that sets a precedent for the advent of building innovation interna-tionally from the 20th Century. La Halle Freyssinet has been named after the engineer, Eugène Freyssinet, and was constructed during theperiod of 1927-1929 alongside public works projects in Paris such as the Gare d’Austerlitz. La Halle Freyssinet represents 20th Century pat-rimony that utilizes an early example of pre-stressed concrete for construction of architectural enclosure with grand volumes totaling18,000 square meters. The interior spaces are unique, timelessly elegant and magnificent. As International heritage experts meet duringthe Assembly meeting at UNESCO, it is strongly recommended that the building and all of the 18,000 square meters of interior space bepreserved in its full integrity and that action be taken to ensure its full protection now and in the future. At the time of this writing, this ini-tiative has gained the attention of the Parisian municipality and plans to alter or demolish the Halle Freyssinet have been stopped.We are headed in a dynamic direction in the next few years. Our initiatives include meetings and study tours, symposia, and the writ-ing of a technical publication on conservation engineering. Through these initiatives and through future newsletters I hope to person-ally get to know each and every one of you. Sincerely,Stephen J. KelleyPresident - ISCARSAH

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August, 2012

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Photo: Wikipedia Commons

ork continues on monitoring,diagnosis and stabilization of

three of the five Franciscan Missions of San Antonio, Texas, which were re-cently nominated the UNESCO WorldHeritage List.Working with conservators at the Mis-sion San Antonio de Valero (1724), mostcommonly known as the site of the battleof the Alamo (1836), a first phase mortarsurvey has been completed, and plansare being made to extend this to a full

INDEX

Message of the President of ISCARSAHStephen Kelley

News from Iscarsah MembersPatrick Sparks, Franciscan Missions ofSan Antonio, TexasDavid Yeomans, The gates of TrinityCollege, CambridgeRamiro A. Sofronie, The endless columnKari Avellan, News from Finland

Iscarsah MeetingsLa Habana ProgramOrestes M. del Castillo del Prado, Visitaa la Escuela Taller “Gaspar Melchor de Jovellanos” en La HabanaWilliam A. Dupont, Visit to ErnestHemingway’s HomeOrestes M. del Castillo del Prado, Visitaa las Escuelas Nacionales de ArteVisita al Estado Mayor del ConsejoNacional de la Defensa Civil y alInstituto Nacional de MeteorologíaNicolas Cheval, Réunion du Comité ISCARSAH à ParisPierre-Yves Caillault, Meeting au Pérou20-24 Avril 2012

Scientific reportsStephen Kelley, Saving The GingerbreadHouses of HaitiToshikazu Hanazato, Report on theDamage to the Cultural Heritage. The Great East Japan Earthquakeof March 11, 2011Alessandro Baratta, Earthquake predictionand seismic prevention for architectural heritage

Iscarsah newsletter n. 1/2012

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News from Iscarsah Members

International Scientific Committee on theAnalysis and Restoration of Structures ofArchitectural Heritage

website:http://iscarsah.icomos.org/

facebook:https://www.facebook.com/pages/IS-CARSAH/263710868630

linkedin:http://www.linkedin.com/groups/IS-CARSAH-Structures-Architectural-Her-itage-3930057

Newsletter n. 1August, 2012ISSN 2306-0182

Editor: María Margarita Segarra LagunesVia Emanuele Filiberto, 19000185 Roma (ITALY)

email: [email protected]

materials-conservation database, alongwith other diagnostic surveys. A majorstructural stabilization has been com-pleted at Mission San Juan de Capistrano(1731), after several years of study andmonitoring of expansive soil movement. A nearby photo shows the large archingcrack that was caused by the movement.Structural monitoring continues at Mis-sion San Francisco de la Espada (1741).Espada and San Juan remain activeCatholic churches.

Franciscan Missions of San Antonio, TexasPatrick SparksSparks Engineering, Inc.

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pair of gates might seem anunlikely subject for structuralrestoration but these date

from the sixteenth century andeach leaf weighs 3/4 tonne. Apartfrom any intrinsic historical signif-icance they may have in their ownright, the gates of Trinity Collegein Cambridge, form the entranceto an important group of historicbuildings. They had suffered theravages of time and there hadbeen major repairs in the nine-teenth century, but recently it be-came clear that new repair workwas needed when the gates beganto drag on the ground. This wasbecause they had dropped and,apart from the forces required toovercome friction at the ground,the gates came into contact at thetop before they were completelyclosed. As the college porters ap-plied forces to close the gatesthere was some out of plane bend-ing which resulted in fracture ofone of the meeting stiles. Apartfrom that the need to deal with theproblem became urgent when thetop hinge on the north gate broke,so that the gate was now hangingon only two hinges rather than theoriginal three.

The gates required more than thestructural repairs because theywere covered with linen-fold deco-ration, which also needed repair(Fig 1). The major timbers wereheld together with large iron rivets,which an x-ray survey showed to bein good condition. These wouldhave to be drilled out if they had tobe removed so that it was desirableto limit the extent to which thegates had to be dismantled. Thisruled out the first proposal for deal-ing with the structure of the gate.An engineer engaged by the collegehad suggested using steel strapsbetween the top hinges and the toeof each gate and a specialist con-tractor was asked to tender for therepair work on that basis. Howeverhe pointed out that such strapswould need to pass behind majortimbers requiring the almost com-plete dismantling of the gates andproposed an alternative solution,which was to fasten a steel bracketto the hanging stiles to pick up theweight of each gate.

Iscarsah newsletter n. 1/2012News from Iscarsah Members

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The gates of Trinity College, CambridgeDavid YeomansThe gates of Trinity College, CambridgeDavid Yeomans

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Fig. 1

Fig. 2

A ‘back of envelope’ check sug-gested that it would be a feasiblesolution though I only had a cou-ple of photographs to look at. Atthat time the gates were still in po-sition so that no detailed examina-tion of the timbers had beenpossible. Nevertheless we were in-structed to proceed on that basis.Detailed examination of the gateshad to wait until the first of themhad been taken down and carriedto the workshop.

It was only then that the conditionof the gates that must have neces-sitated the nineteenth century re-pairs and the extent of thechanges then made could be ap-preciated. Clearly both the bottomrail and the hanging stile of bothgates had rotted and had been cutoff. Examination of the growth rings on the remaining part of the rail on the south gate showed that approxi-mately half of the rail had been cut away. The new timbers added below the remaining timbers of the bottomrails were held in place by wrought iron straps. The replacement timbers for the bottom of the hanging stileshad been lap jointed onto the original timbers which had been cut back to receive the new pieces. These sur-faces offered a means of fixing tothe gate without any additionalcutting of original timber eventhough they were clearly not ideal.Figure 2 shows the bottom cornerof the north gate and Figure 3 thatof the south gate.

Rather than immediately adoptingthe proposed scheme my first ques-tion was to consider how the struc-ture of these gates had beenworking for four hundred years. Theideal would have been to restoresomething like the original mode ofbehaviour if at all possible althoughthe support forces provided by thehinges had clearly changed. Thegates were each hung on threehinges, so how the support forceswere distributed originally can onlybe a matter of speculation. As thebottom rails had been cut back andnew pieces fastened on, this re-quired some refixing of the bottomhinge so that it seems likely thatthere was a period when the gateswere hanging on the top and mid-dle hinges. More recently the hingepintle of the north gate had brokenso that was now hanging on themiddle and bottom hinges. Concernwas that misalignment of the hingeshad been producing out of planebending in the gates and it was re-solved to hang them on the tophinges and pins below the gates.

The body of the gate comprisedledges and muntins with half lapjoints and vertical boards be-


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Fig. 3

Fig. 4

tween the muntins (Fig. 4). Examination of the jointsbetween these framing timbers suggested that thegates had been working by diaphragm action pro-vided by the resistance to rotation of the joints be-tween the muntins and ledges. The vertical boardsmay have originally contributed to this but theirshrinkage now made them ineffective. The optionsseemed to be to design steel brackets as originallyintended or to demonstrate the possibility of relyingupon diaphragm action. The latter held open thepossibility of the least intrusive repair strategy andwas seriously considered. It would have been neces-sary to demonstrate that forces within the di-aphragm were within acceptable limits and that themethod of load transmission was sufficiently robustto cope with changing moisture content within thetimber. However, there were practical difficulties thatwere to prevent the full exploration of this mode ofaction. The fixing of the lower pivot required somesteelwork to be attached to the gate. It was alsopointed out that both college and conservation au-thorities were anticipating the steel bracket to beused, so that a change of repair strategy would havecaused delays.

Design of the steel bracket for each gate was simple.It was a T shaped plate to carry the weight of the gatewith a socket at the end into which the bottom hingepin could be screwed. This hinge pin was to go into abox set in the ground where the receiving socket couldbe adjusted for position. The position of the plate wasdictated by the position of the surface on the hangingstile to which it had to be attached. The basic plan wasto use this surface to attach the short leg of the Lshaped steel. so that it could then be concealed by theoriginal repair timber. Figure 5 shows the steel in po-sition on the north gate. The design problem was toarrange sufficient fixings to carry transfer the momentfrom the steel plates into each stile taking account ofthe condition of the timber. The plate also had to bewrapped round the back face of the stile to stiffen itagainst the bending moments produced by the eccen-tricity of the hinge pin.

The area for fixing was very small in both cases andthe condition of the timber variable. In both casesthere were holes where there had been bolts holdingthe repair timber in place and there were also mor-tice pockets in the timber of the north gate. Howeverit was possible to find sufficient room to use screwsacting in shear to fix the plate without additional cut-ting of the timber. On the south gate there were nomortices visible in the surface available, and drilling showed there were none under it, but the area avail-able for fixings was much smaller. Initially the holes made for the wrought iron bolts in the nineteenth cen-tury repair seemed to offer a simple solution; we would simply replace wrought iron with steel of a suitablediameter. However, there was a split round one of the holes, which not only prevented its use for carryingload but necessitated a completely different method of load transfer. It was necessary to shape the plate sothat screws in withdrawal could be used at that end. The lever arm between the two forces was so reducedby this that a pair of bolts in the original holes at the other end would have been insufficient. In that case itwas necessary to cut a slot in the stile to take the plate up above the nineteenth century reduction in thesection in order to obtain a sufficient lever arm between fixings.

Design of the fixings was carried out within the constraints on spacing, end and edge distances specified in cur-rent design codes. It should also be noted that the design was also dependent upon having confidence in thehigh level of skill available in the workshop. Stainless steel was used for plate and screws. At the time of writ-ing the north gate has been repaired and hung in position while work on the other is being completed in theworkshop. It should be in position by the time you read this.


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Fig. 5

he Column has been erected 75 years ago in only three months, be-tween 15 August and 15 November 1937, in Targu Jiu, Romania, by the

sculptor Constantin Brancusi (1876-1957). It is the only endless column inthe World and belongs to the Memorial devoted to the heroes of the FirstWorld War 1914-1918 (Fig. 1).The Column together with the Table of the Silence, the Alignment ofStools and the Gate of the Kiss form an architectural and urban ensembleextended along a distance of 4 kilometers and called by sculptor the Alleyof the Souls. In this Memorial an existing orthodox church, which provesthe east-west orientation of the ensemble, was also included Each group of sculptures has been endowed with a precise function. Forinstance, the massive Gate, like a small triumphal arch, does not refer tothe ordinary, real kiss by lips. The image carved in travertine is suggest-ing the fascinating idea of the kiss by perfect superposing of the two in-volved faces, according to the vertical line of gravity, the eyes alsoincluding. At its turn the Endless Column, as a funeral monument, wassupposed to create a link between Earth and Heaven. It means a virtuallink devoted to the transcendence of heroes souls, detached from theirmaterial bodies. This is why the feature of the Column of being endless oreven infinite was tacitly accepted from the very beginning not only as anatural condition, but also as a necessary one. When the erection wascompleted under his careful supervision, Brancusi asked to his team topaint the Column in the yellow colour of wheat fields in ripe. In the sametime he stated to his countrymen: You are not able yet to realize what Ihave left to you! Then quietly he left for ever to Paris. During thosetwenty years that followed, from 1937 to 1957 when he passed in eternity,he did not produce any new piece of art. The Endless Column was his lastmasterpiece.The late architect Silvia Paun ascribed a megalithic stylization to that ar-chitectonic ensemble of modern art. She identified the Table of the Si-lence and its twelve Stools with a Cromlech or a Circular Temple ofMenhirs, the Alignment of Stools with a Linear Temple of Menhirs hori-zontally extended, the Gate of the Kiss with a Dolmen, and the EndlessColumn with a Linear Temple of Menhirs vertically extended. Once these

functions recognized as such, the Ensemble of Targu Jiu was integrated with other vestiges of World MegalithicCultures like Carnac in France, Stonehenge in Great Britain and Sarmisegetuza in Romania. It was for the firsttime in History when the Modern Sculpture at such large scale reflected so faithfully the ancient art expressedby stone not only in shape, but mainly in the meaning of their messages. In fact, most of Brancusi sculptureshave been shaped in natural stone (Fig. 2). In his ambition of genius to reach the Heaven Brancusi was aware what happened on the Babel Tower (Genesis

11, 1-9). He understood whatphilosopher Mircea Eliade alreadywrote that only the human soul isable of transcendence i.e. passingfrom material space to the spiri-tual one. Brancusi assumed from


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The endless columnRamiro A. SofronieEmeritus Professor, Bucharest, Romania - Chair holder of UNESCO Chair #177

Fig. 1

Fig. 2

his birds that the main obstacle in reaching the Heaven might be gravity. That discovery also disclosed the fail-ure of biblical attempt on Babel Tower. Gravity contents of matter were well known from long time. Aristotle(384-322 BC) believed that gravity was one of the two forces of universe, but only two thousand years later, in1687 Newton, in Book III of his Principia Mathematica, published the universal law of gravity.This law perfectly suits to the approach of Brancusi about the symbolic flight of his birds. Mircea Eliade wrotethat by those statues Brancusi expressed the essence of the flight by coincidentia oppositorum. Unfortunately forBrancusi, Newton’s law does not apply to human souls. Gravity remains limited to human bodies, while for theimmaterial souls he was obliged to find another law available to human beings. Obviously, something essen-tially free of gravity and different by imponderability. This is why, by an intuition of genius, Brancusi decided touse that what today is currently called Topology or analysis situs, an advanced science of shaping. Since theyear 2001, when the UNESCO Congress was held in Paris, two topological concepts were identified in the act ofcreation of the Endless Column. Later a third one was added, and the door of knowledge remains opened forother discoveries.First concept is anthropomorphism and refers to the stylization of humans. Traditionally, memorials like thosefor Trajan in Rome, Napoleon in Paris, and Nelson in London were built as massive stone columns, all higherthan 30 m and each supports on its top a statue. Brancusi never imitated other creations. For the funerary monu-ment in Targu Jiu his option was a slender column in a modular composition of less than 30 m in height. Along asteel core a score of identical modules of cast iron were successively laid one over the other in the vertical direc-tion of gravity. According to their statute of representing young heroes, the modules were shaped like stylizedcoffins. Each module is represented by an isosceles decahedron with four vertical plans of symmetry and a hori-zontal one at the middle. That decahedron satisfies the topological theorem of Euler between facets, peaks andedges F + P = E + 2, namely 10 + 12 = 5 x 4 + 2. The height of each module is 180 cm; the middle square is 90 x 90while the two end squares are 45 x 45, following the proportion 4:2:1.Due to the existing horizontal plan of symmetry each decahedral module can be regarded as composed by twoidentical hexahedral units. They were used by Brancusi in composing the Column by 15 full modules and 2halves located at the two ends what is equivalent with 16 modules. By adding at Column base a short guardlength its total effective height is h = 29.35 m. Therefore anthropomorphically, the Memorial Column consists in asuccession of standing identical coffins accordingly stylized.The second concept is an idiomorphic one being related to the perfection of shaping. In the theory of aestheticsthe unit for measuring the perfection of monuments and evaluating thus the beauty of human creations is thegolden mean or triangle, also called the sacred proportion, φ= 1.618. It was used, for instance, to the CathedralNotre Dame of Chartres in France (1134-1220), but also to the Petrindu Church in Romania (1612). In the case ofdecahedral module created by Brancusi on each of its facet four golden triangles were identified. That meansonly a single module contains 4 x 8 = 32 golden triangles, while the whole Column is based on 8 x 8 x 8 = 512golden triangles. That remarkable figure explains why Brancusi asked for painting his Column in a golden yellowcolor. By comparison, Cheops Pyramid in Giza, Egypt (2601-2515 B. C.), which geometrically is a pentahedron,also satisfying Euler’s theorem 5 + 5 = 8 + 2, contains only four golden triangles, located two by two in the verti-cal plans of symmetry, perpendicular on base sides. A surprise comes from Mesopotamia.The reconstituted dimensions of the former Babel Tower, erected as a ziggurat probably by the King Hammurabithe Great (1792-1750 B. C.) are 90 x 90 x 90 meters and they coincide, at the scale of 1:100, with Column’s hexahe-dron of 90 x 90 x 90 centimeters. That means that the Babel Tower contained 4 x 4 = 16 golden triangles what ex-plains its worldwide and long lasting fame. As far as the Column height is concerned it was not at all randomlychosen. It is easy to observe that 16 modules mean 10φwith an error of only 1,125 %, what proves the goldenchoice of Column height. But what is really amazing is the height h = 29,35 m adopted by Brancusi for his Col-umn in Targu Jiu differs with less than 1 % by the diameters d = 29,426 m of the two megalithic circular sanctu-aries in Stonehenge, UK and Sarmisegetuza, Romania. Therefore the idiomorphic concept of shaping is fulfilled. The third concept is auto or isomorphism and explains the unique quality of being endless. In composing his Col-umn out of decahedral modules Brancusi has used the topological law of self-generating the forms based oncongruence or the well knowing mirroring effect. Indeed, after repeating several times the congruence of mod-ules, the topological law of isomorphism came in force consecrating the endless feature of the Column. In fact,


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mirroring effect caught the attention of thinkers long ago. For instance, in Egyptian Mythology the beginning oftime Zep Tepi was marked in the year 11,451 BC. when the Milky Way and the Nile have perfectly mirrored eachother. Later Plato (429-347 BC), in his book Republica, recommended to all artists to use, in doing their creations,looking glasses. Much stronger influence of this effect on humans came from the Myth of Narcissus. According toGreek Mythology, Narcissus saw his own reflection in the water and fell in love with it. Unable to leave thebeauty of his reflection, Narcissus died. A classic version of this legend was included by Ovid in his Metamor-phoses, and in modern times, Oscar Wilde wrote The Picture of Dorian Grey. Although Brancusi never confessed,it seems he was the only human being in the World who clearly understood that the beauty seen by Narcissus inthe pool comes from the lack of gravity. Any human body liberated by the confinement of gravity feels displayinga brighter mirrored image than the original one. It looks like the mirror bears the key of immortality. Thus Bran-cusi discovered exactly what he arduously needed for reaching the target of his Memorial: keeping symbolicallythe bodies in coffins and allow the souls to leave the material space along the visible unlimited way, opened byrepeated congruence of modules. Brancusi expressed his art by Geometry, but he consequently created throughTopology. Therefore the concept of auto or isomorphism has a strong support in history and it definitely provesthat topologically the Column is really endless. In the year 1996 the distinguished professors Giorgio Croci and Stephen Kelley, as experts of UNESCO and WorldMonuments Fund, have inspected the Memorial in Targu Jiu and supported the restoration program for the End-less Column. The work has been successfully completed, and now the site is opened for public. The whole en-semble is a wonder worth to be seen by anyone interested in the mysteries of life.


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Personal projects of KAREG Consulting Engineers

The shipyard of Sveaborg(Suomenlinna)The shipyard is built partly onSwedish time and partly on Russ-ian time, when Finland was aGrand Duchy of Russia. After theindependence of Finland (1917-12-6), just before the World WarII the shipyard was deepened byblasting and lots of concrete workdone. KAREG is in charge of thequay wall next to the floating doorof the lock (Fig. 1, Fig. 2).

Ice Hockey World Champi-onship 2012 The expansion of Hartwall Arena inHelsinki was built, because IceHockey World Championship wasplayed in Helsinki and Stockholm.KAREG was in charge of the proj-ect as technical consulting engi-neer and especially as residentengineer for rock strengthening,foundations and concrete struc-tures. The thickness of rock wallbetween the Arena and the rockrestaurant was partly only 1.69 mand the buckling height about5.0…5.5 m. The arch has of coursea horizontal load (Fig. 3).

News from FinlandKari AvellanKAREG Consulting Engineers

Fig. 1 Fig. 2

Fig. 3

Iscarsah newsletter n. 1/2012Iscarsah Meetings: La Habana 2011

ISCARSAH Meeting: Havana, Cuba 2011Workshop: Earthquakes and HurricanesResponse and PreparednessMay16-17, 2011; College of San Geronimo, Havana, Cuba

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Visita a la Escuela Taller “Gaspar Melchor de Jovellanos” en La HabanaOrestes M. del Castillo del PradoICOMOS Cuba

na vez concluidas las Sesiones deTrabajo del Taller Internacional “Te-rremotos y Huracanes. Respuesta y

Preparación” organizado por ISCARSAH,llevado a cabo por primera vez en La Ha-bana, Cuba, el Comité Organizador Cubanocoordinó una serie de visitas a institu-ciones y lugares de interés relacionadoscon los objetivos de la conservación delpatrimonio construido, su respuesta ypreparación ante fenómenos naturales.Una de esas visitas se realizó el 19 demayo 2011 a una de las sedes de la EscuelaTaller “Gaspar Melchor de Jovellanos”, dela Oficina del Historiador de la Ciudad deLa Habana, en la que se preparan jóvenesen los diferentes oficios de la construcción

con énfasis en la recuperación de métodosy procedimientos tradicionales de ejecu-ción de obras, principalmente en el campode la conservación histórica.En la Escuela, los visitantes acompaña-dos por miembros de ICOMOS Cubafueron recibidos por personal de la Di-rección de la Escuela, quienes explicaronlos contenidos de la enseñanza que seimparte y la forma teórico-práctica enque se desarrolla, dando desde losprimeros momentos del inicio de sus es-tudios una participación directa de losestudiantes en las obras de recuperacióndel patrimonio edificado en el CentroHistórico de La Habana Vieja, un entornourbano que permite apreciar el carácter

de la arquitectura colonial y los esfuer-zos que se realizan para preservar monu-mentos que datan de varios siglos deexistencia.Los distinguidos miembros de ISCARSAHque participaron en la visita pudieronapreciar, desde muy cerca, cómo losjóvenes estudiantes se preparan en eltrabajo del taller, con el soporte de mate-rias teóricas que le dan el conocimiento ydominio del oficio elegido que, al final deun período escolar de tres años, les per-mite alcanzar el certificado de obrero ca-lificado y les garantiza empleo en lasentidades que tienen a su cargo la reha-bilitación del Centro Histórico de La Ha-bana Vieja.

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Iscarsah newsletter n. 1/2012 Iscarsah Meetings: La Habana 2011

Miembros del ISCARSAH de visita al Castillo de la Real Fuerza en La Habana.

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uring our ISCARSAH meetingin Havana, Cuba, in thespring 2011, a small group of

members made the trip out toErnest Hemingway’s home one af-ternoon. Hemingway called it FincaVigía, meaning farm with a view,and he lived there from 1939 to1960, during which time he wroteFor Whom the Bell Tolls, The OldMan and the Sea, A MoveableFeast, and Islands in the Stream.The house and grounds becameMuseo Hemingway in 1963. I ledthe group due to my friendship withthe museum’s Director, Ada RosaAlfonso Rosales, and her staff.

In the spring of 2005 Hemingway’sFinca Vigia was nominated to the“11 Most Endangered List” of theU. S. National Trust for HistoricPreservation. This led to a long-standing and fruitful partnershipbetween the Finca Vigía Foundationin Massachusetts (dedicated toconservation of Hemingway’s homeand the documents containedthere), the National Trust, and theCuban government agency respon-sible for management of museumproperties, the Consejo Nacionalde Patrimonio Cultural (CNPC). Ateam of US professionals beganvisits in fall 2005. When the collab-oration began, I had then served 9years as the architect for the Na-tional Trust’s historic sites. I be-came the leader of this “technicalteam” and developed great friend-ships over more than a dozen vis-its that followed.

So, when ISCARSAH members ex-pressed interest in a visit, it was asimple matter to contact the mu-seum and make arrangements fora visit.

The museum Director, Ada Rosa,met our ISACARSAH group withopen arms and engaged us in aconversation on museum manage-ment issues. She was pleased toshow us the museum’s recent ac-quisition of Hemingway’s 1957Chrysler convertible. She uncov-ered the relic, lacking an engineyet largely intact, for a few quickphotos. Later our group took astroll past Hemingway’s deep seafishing yacht, Pilar, now in perma-


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nent dry-dock on the site and weenjoyed the beauty of the land-scape Hemingway inhabited. Theswimming pool with its twin ca-bana structures was a highlight, aswas the shaded patio with a com-manding view across fertile valleysto distant Havana 10 miles northon the coast. Ernest Hemingwaywas 39 years old when he rented

Finca Vigía with his 3rd of fourwives, an old farm estate that hesoon purchased to be his home.Twenty-one years later he leftCuba in the summer of 1960 onone of his many trips abroad, in-tending to return. What remains inCuba are the home and landscapehe inhabited plus all the tangibleelements of his life – first edition

A visit to Ernest Hemingway’s HomeWilliam A. Dupont, AIADirector, Center for Cultural Sustainability at UTSA College of Architecture


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Iscarsah Meetings: La Habana 2011

books, letters, record player, hunt-ing jackets, fishing rods, liquorbottles, his black Royal typewriterand stacks of magazines by theside of his bed – all arranged asthey were when he shut the doorin 1960. The house sits now as atime capsule of Hemingway’s life,essentially unchanged since theday he departed for a trip to Spainfrom which he never returned.

The US Technical Team continuesto assist our Cuban colleagues inan advisory capacity under a spe-cial license from the United StatesTreasury Department.

The authorization to travel toCuba, work with Cuban museumprofessionals, architects, engi-neers, and conservators on thesite, and to engage in documenta-tion and assessment of the preser-vation needs of Finca Vigía is anextraordinary thing due to the lackof diplomatic relations between thetwo neighboring countries.

Cuban and American professionalsin the field of heritage conservationhave never had specific interactionin Cuba. The Technical Team is theonly group of American design pro-fessionals sanctioned to work inCuba since the 1959 Revolution.

The care of museum properties is acontinuous effort. Much has beenaccomplished since that first visit in2005, and an array of future proj-ects await the joint team of profes-sionals working to preserveHemingway’s legacy in Cuba.


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Visita al Estado Mayor del Consejo Nacional de la Defensa Civil y alInstituto Nacional de MeteorologíaOrestes M. del Castillo del PradoICOMOS Cuba

Como parte importante de las activi-dades del taller Internacional “Te-rremotos y Huracanes. Respuesta y

Preparación” los participantes hicieronuna visita al Estado Mayor del ConsejoNacional de la Defensa Civil. Allí el Jefedel Estado Mayor les dio una amplia expli-cación sobre el funcionamiento del Con-sejo Nacional de la Defensa Civil y lasacciones que se llevan a cabo en la pre-vención de afectaciones a la población encaso de desastres naturales, lapreparación general ante esas situacionesy la respuesta que se da para resolver losproblemas que esos eventos ocasionan.Como complemento, tres especialistas de

esa institución ofrecieron conferenciasrelacionadas con el trabajo que da lugar ala atención a la población en esos casos ylas medidas que se aplican para minimizary hasta evitar afectaciones de caráctergrave, una de las conferencistas participóen las Sesiones del Taller. A continuaciónlos participantes visitaron el Puesto deMando y allí recibieron información de-tallada del trabajo que se realiza, enforma permanente, en todo el país parapreparar a la población y disminuir ries-gos y pérdidas, estableciendo un sistemade información dirigido a ese propósito.Una vez finalizada la visita a la DefensaCivil, los participantes se dirigieron al ve-

cino Instituto Nacional de Meteorología,donde el Director del Departamento dePronósticos explicó el detallado sistemade información que se ofrece como pre-vención de situaciones graves en caso dehuracanes, desde el momento en queestos comienzan a formarse, su trayecto-ria y características principales, su paso através del país por medio de partes que setransmiten por todos los medios de comu-nicación nacionales.El Director ofreció una conferencia sobrelos huracanes en Cuba que se completócon un amplio debate sobre el tema en elque los visitantes participaron activa-mente.

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Visita a las Escuelas Nacionales de ArteOrestes M. del Castillo del PradoICOMOS Cuba

l conjunto que constituyen las Escue-las Nacionales de Arte, es un icono dela arquitectura del movimiento mo-

derno en Cuba y ha despertado desde susetapas iniciales un gran interés por mu-chos y diversos aspectos, tanto formalescomo funcionales y sobre todo por la inte-gración de los edificios en el medio en quehan sido construidos y también porquecada uno de ellos encierra un conceptosignificativo de organización del espaciocon profundo sentido urbanístico.En la continuidad del programa de visitaspreparado para los participantes del TallerInternacional “Terremotos y Huracanes.

Respuesta y Preparación”, un grupo deellos realizó un largo e intenso recorridopor el lugar el día 19 de mayo, tras con-cluir las Sesiones de Trabajo que tuvieronlugar para exponer y discutir un númeroimportante de ponencias científicas pre-sentadas, tanto por los miembros de ISCARSAH que concurrieron al Tallercomo por los profesionales cubanos queexpusieron sus propias experiencias en larespuesta y preparación ante los hura-canes y terremotos que, con cierta periodi-cidad, afectan al país.Los visitantes recorrieron la totalidad delconjunto pudiendo apreciar las rehabilita-

ciones hechas a las Escuelas de Artes Plásticas y Danza, así como la inconclusaEscuela de Artes Escénicas, y las Escuelasde Música y Ballet, estas últimas en es-tado ruinoso y pendientes de que seacometan las necesarias intervencionesconstructivas para rescatar y poner enfuncionamiento esos inmuebles.En términos generales el grupo que visitóla obra pudo conocer “in situ” todas suscaracterísticas constructivas que siguen lapauta de la ejecución de bóvedas tabi-cadas, una técnica heredada de maestroscatalanes, que fue introducida en Cubapor ellos, desde hace más de un siglo.

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e comité ISCARSAH s’est réunià Paris le 28 novembre et 2décembre 2011 en marge de

l'Assemblée générale ICOMOS In-ternational qui s’est tenue cettemême semaine au siège del’UNESCO. Deux visites commen-tées ont été organisées à cette oc-casion. Les membres du comitéont été invités à découvrir la facecachée du dôme du Panthéon enprésence de l’Architecte en Chefdes Monuments Historiques,Daniel Lefevre, qui a exposé lesprincipes du projet de consolida-tion conduit avec la collaborationde Carlo Blasi et du LaboratoireCentral des Ponts et Chaussées.L'étude menée, appuyée sur desrecherches exhaustives des docu-ments historiques, a permis d'i-dentifier la nature structurelle desdésordres relevés sur les façades,les grands arcs et la triple coupole.Les observations et calculs réalisésont révélé une sensibilité impor-tante des maçonneries aux défor-mations sous charges gravitaireset thermiques, en particulier sousles effets de la poussée des voûteset des grands arcs, accentuée parla présence d'un revêtement enpierre agrafée et des joints trèsfins.La plupart des désordres se sontmanifestés dès la construction del'édifice et les plus actifs sont situésau niveau des tribunes et des ga-leries hautes. Cette vulnérabilitédes structures a été accrue par uneabsence d'entretien dans le tempsdes couvertures qui a entrainé desentrées d'eau considérables dansles parties hautes de la structure,ainsi que des phénomènes de con-densation qui ont eu raison desnombreux éléments métalliques quicomposent les maçonneries.Les travaux de consolidation quiseront réalisés dans les prochainesannées porteront donc sur la ré-fection des couvertures, la réduc-tion des effets thermiques et sur letraitement de la corrosion des élé-ments métalliques internes ainsique sur la mise en place d'un chaî-nage de sécurité des coupoles.Le comité était ensuite attendu aupied de la Tour Eiffel par StéphaneRoussin, chef du service des struc-tures, qui a exposé les probléma-tiques quotidiennes posées par

Iscarsah Meetings: Paris 2011

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Réunion du Comité ISCARSAH à ParisNicolas ChevalUnanime architectes

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l’entretien et la conservation de cemonument hors normes. Le princi-pal enjeu évoqué est une coursecontre la montre pour limiter lacorrosion des éléments métalliquespar des travaux de mise en pein-ture sous conditions extrêmesréalisés tous les 7 ans.Lorsque certains éléments sonttrop détériorés, leur replacementest parfois envisagé. Un modèlenumérique aux éléments finis del'édifice a été réalisé pour identifierles niveaux de sollicitations danschaque partie de l'édifice et éva-luer les conditions provisoires demise en œuvre des renforcementsou remplacements. Ce dernier estcomplété par un système de sur-veillance automatisé des déforma-tions de la structure. A l'issue decet échange, une visite de l'édificea permis de prendre la mesure dela tâche à accomplir.


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Iscarsah Meetings: Cuzco/Lima 2012

n tant que membre récentd’ISCARSAH, il me revient toutnaturellement de faire ce bref

compte rendu de notre « escapade »au Pérou.Ce meeting s’est déroulé en intro-duction de la « Terra Conference »qui a eu lieu à Lima du 23 au 27Avril 2012.

Voyage à Cuzco et Machu Picchu20-23 AvrilParticipants :Stephen Kelley (Président), USA ;Görun Arun, Turquie ; Maria Margari-ta Segarra Lagunes, Mexique/Italie ;Lyne Fontaine, Canada ; In-SoukCho, Corée ; Alexander Salenikovich,(Russie) Quebec ; Kari Avellan, Fin-lande ; Ramiro Sofronie, Roumanie ;Pierre-Yves Caillault, France.De nombreux participants étaientaccompagnés (notamment pour lesvisites de sites et monuments).Les sites et monuments visités in-téressent principalement la périodeprécédant l’arrivée des Espagnolsau Pérou (vers 1530) ; ils té-moignent d’une civilisation éradi-quée par les conquistadors (etleurs alliés ). Ces derniers sont en-core perçus par les péruviens com-me responsables de l’éliminationsans pitié de la richesse de la cul-ture passée et de leurs principauxreprésentants (notamment lesprêtres). Les lieux visités évoquentles rites particuliers de ce peuplecomme la momification mais c’estbien sur l’architecture et sa conser-vation qui intéresse avant toutl’ensemble des participants.Ces sites montrent à quel point les« Incas » ont tiré parti des disposi-tions naturelles pour les compléter,souvent de façon spectaculaireavec des constructions en grandappareil dont la mise en œuvrenous laisse perplexe. Des blocs degranit de très grandes dimensions(certains semblent peser plusieursdizaines de tonnes) et de formestrapézoïdales irrégulières sont ap-pareillés avec des joints très finsqui semblent dépourvus de mortier.Les parois ainsi construites présen-tent un fruit prononcé et régulier cequi nous prouve que ces réalisa-tions répondent à une conceptionprécise et que le mode constructifemployé est parfaitement maîtrisé.Quel procédé de mise en œuvre apermis de construire des maçon-neries aussi spectaculaires (laforteresse de Sacsayhuamán estconstruite avec des blocs pouvantpeser plusieurs centaines de ton-

Meeting au Pérou 20-24 Avril 2012Pierre-Yves CaillaultArchitect ACMH

nes) ? Aucun texte, aucune illustra-tion ne permet de le savoir.Nombre d’entre nous s’interrogentsur la capacité de ce type de cons-truction à résister aux tremblementsde terre, principale menace pour lepatrimoine bâti aujourd’hui. Noussommes dans une région du mondeoù les séismes sont fréquents, con-séquence de la « tectonique desplaques ». Ce même phénomènepourrait expliquer la présence desable, voire de sel au cœur desmontagnes ; les salines de Marascréent la surprise au détour du lacetd’une route de montagne. Le prosélytisme indien dont font

preuve nos différents guides nenous empêche pas lors d’une étapeaux environs de Cuzco, d’allerspontanément visiter le chantierde restauration d’une église de lapériode Espagnole. Ce monumentqui a manifestement souffert d’untremblement de terre fait l’objet detravaux importants : reconstruc-tion de la toiture selon les métho-des traditionnelles (charpente enbois à peine équarris, lattis enroseau enduit de plâtre en sous-face et d’argile en surface, le toutblanchi à la chaux ; couverture entuiles neuves traditionnelles), res-tauration du décor intérieur.

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La « Vallée sacrée des Incas » nousmena sur plusieurs sites jusqu’àMachu Picchu. Au cœur des mon-tagnes, ce site célèbre et spectacu-laire confirme l’usage du modeconstructif « trapézoïdal » : des ou-vertures aux jambages inclinés, desmurs avec un fruit prononcé cons-truits en grand appareil plus oumoins régulier, une pose à jointsvifs, avec de petites pierres inclusesdans des réservations taillées à larencontre de plusieurs blocs et quisemblent faire office de clé.Ce site exceptionnel, très restauré(certaines restitutions semblent dis-cutables) demande un entretienconstant et pose la question de laconservation des ruines aménagéespour permettre une grande fré-quentation touristique.

DiscussionsNous réfléchissons au meilleurmode de communication entremembres d’ISCARSAH ; certainsévoquent « face book » mais noussommes plusieurs à ne pas y êtrefavorables à cause des dérives quipourraient y être associées (intru-sions de messages parasites,fausses informations, images dif-fusées sans le contrôle du sig-nataire…) ; nous évoquons Linkedincar plusieurs d’entre nous y sontinscrits.La question de l’admission de nou-veaux membres pose le problèmedu maintien des membres dontl’activité s’est progressivement dé-tachée des sujets qui nous réunis-sent. Nous évoquons la possibilitéde procéder à une mise à jourrégulière des CV de chaque mem-bre afin que la capacité d’expertised’ISCARSAH soit garantie. A ce pro-pos, la faible représentation fran-çaise est soulignée.Pour mieux connaître et identifierchacun d’entre nous il serait perti-nent d’éditer une liste des membresavec leurs photos.Un projet de livre sur les fonde-ments et l’activité d’ISCARSAH estévoqué. Nous proposons que letexte fondateur (sorte de charte)soit édité dans les trois languesd’ICOMOS : anglais, français, es-pagnol. Rappelons que chaquelangue véhicule des concepts quipeuvent enrichir nos réflexions.Nous proposons de travailler à latraduction française.

Le projet de News Letter que nous avons évoqué peut enfin voir le jour grâce à l’initiative de Maya que nous re-mercions. C'est un moyen d'aborder différents sujets de réflexion pour une diffusion plus large qu'aux seulsmembres d'ISCARSAH.Je suis heureux de participer à la rédaction du n.1.

he Caribbean island nation ofHaiti is home to a wealth of his-

toric buildings sites and urban areas.Haiti was colonized by Spanish andFrench settlers, and its built heritagereflects these European colonial in-fluences though few colonial erabuildings remain. Haitians are proudof their revolution, the only success-ful slave rebellion in the westernhemisphere.

The 2010 Haiti earthquake was a cat-astrophic magnitude 7.0 Mw earth-quake that occurred on 12 January. Itsepicenter was approximately 25 kmwest of Port-au-Prince, Haiti’s capital.The Haitian Government estimatesthat approximately 230,000 peopledied, 300,000 were injured, and1,000,000 were left homeless. It is alsoestimated that 250,000 residencesand 30,000 commercial buildings hadeither collapsed or were severelydamaged. Another casualty of theearthquake was Haiti’s cultural her-itage in the form of Gingerbreadhouses (Fig. 1).

The use of the term “gingerbread” de-fines an architectural style that can bedefined by the intricate architecturalornament applied to the facades ofthese residential structures and spansan era starting from late 19th centuryto the early 20th century. Intricatedecorative elements are placed oneaves, balconies and porches, ridgeboards, and door and window trim.Many houses feature steep spires andturrets - an architectural flourish in-digenous to Haiti. Gingerbread houses from the grand to the mundane were designed by Haitian architects trained inFrance and borrowing colombage and pan de bois building techniques from Europe. The houses were found to be con-structed of fired brick, stone, lime and clay mortars, and wood from native forests. However, by the turn of the 20th Cen-tury concrete had been introduced to the island and had all but replaced these elements as the building materials ofchoice. Brick making ceased thereafter. In addition Haiti today is more than 95 % deforested and has no local lumber in-dustry. The lack of these materials and craftsman skills make these structures all the more culturally valuable.


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Scientific reports

Saving The Gingerbread Houses of HaitiStephen KelleyWiss, Janney, Elstner Associates, Inc.

Figure 1 - Madame Vivien Gauthier’s Gingerbread House that was not damaged during theearthquake but suffers extensive termite damage (S. Kelley photo).

Figure 2 - Pictometry image of a Gingerbread House in Port-au-Prince. Since the historic dis-trict was never recorded, these images proved invaluable in identifying each property.

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The purpose of the initial World Monuments Fund (WMF)/ICOMOS Mission was to assess the earthquake dam-age to the Gingerbread district of Port-au-Prince. Led by ISCARSAH member Randolph Langenbach, the teamalso included members Patrick Sparks and Stephen Kelley. This Mission was also made possible by funding andco-sponsorship by Fondation Con-naissance et Liberté (FOKAL), andthe Prince Claus Fund for Cultureand Development.

The assessment included morethan 200 Gingerbread houses inthe district. The assessment wasmade more efficient by the use ofPictometry which made it easy tomap the district using high resolu-tion aerial photography as the lo-cations and quantities of theGingerbread houses were not pre-viously well defined (Figure 2). Theassessment followed a Methodol-ogy and damage assessment formsdeveloped by the team exclusivelyfor use in Haiti.

How did the Gingerbread housesfare during the seismic event?They performed much better thanmuch of the contemporary rein-forced concrete construction (Fig-ure 3). Braced frame structureswere mostly left standing thoughframes that were fit with masonryinfill lost some of this fill. Much ofthe severe damage was to unrein-forced masonry (URM) that was apart of many of these structures.Vernacular construction tech-niques, such as lateral iron tierods, actually enhanced the seis-mic capabilities of these houses(Figure 4).

If the structures were in good re-pair they basically performed well.Damage could be traced to the fol-lowing typical conditions: exten-sive termite damage; inappropriate previous repairs that were incompatible with original framing techniques,and soft lime mortars, and concrete additions that beat against the original house during the seismic event caus-ing damage. The report of this mission, published in English, French and Spanish, can be downloaded for at nocost here:http://www.wmf.org/dig-deeper/publication/preserving-haiti%E2%80%99s-gingerbread-houses-2010-earth-quake-mission-report

Figure 3 - The Cathedral of Port-au-Prince (1917) constructed of reinforced concrete col-lapsed during the earthquake (S. Kelley photo).

Figure 4 - Lateral metal tie rods at the Maison Dufort kept this masonry pilaster (and theentire house) from collapsing (S. Kelley photo).


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Following the assessment, our Hait-ian sponsor, FOKAL, purchased theDufort House and has embarked ona rehabilitation of the building andsite for use as a building craftstraining center.

The Dufort House poses uniquechallenges in that the first floor thatis made of URM has been destroyedbut the second floor and roof remainintact and only slightly undamaged(Figures 5 and 6). As stated byFOKAL President Michèle Pierre-Louis, “If this building can still bestanding then we must save it.”

The original team members are con-tinuing to work on this project andare focusing on seismic retrofittechniques for the first level whichneeds substantial reconstruction.

The Dufort House rehabilitation andseismic retrofit is still in progress.

Figure 5 - The Maison Dufort was left standing despite the fact that the first floor had been destroyed (S. Kelley photo).

Figure 6 - The Maison Dufort being shored for future reconstruction of the first floor walls(S. Kelley photo).

apan ICOMOS National Committee published the preliminary recon-naissance report on the damage to the cultural heritages by the Great

East Japan Earthquake of March 11, 2011. This outlined report was pub-lished on November 20, 2011, being now on the Web Site of Japan ICOMOSas

http://www.japan-icomos.org/pdf/earthquake_report_20111120.pdf

Introducing the features of the devastating earthquake, it described dam-age to not only heritage structuresbut also cultural and natural land-scapes. Furthermore, it dealt withdamage to lots of cultural proper-ties of fine arts & applied crafts. In-troduced in the report, thousandsof cultural heritages were dam-aged. The government started tocollect information of the damageto the cultural properties just afterthe earthquake, and as the result,the statistics of the damage weredescribed in this report. The emer-gency activities have been per-formed at from governmental toprivate level in order to rescue thedamaged cultural properties. Oneyear has already passed since theearthquake. In fact, most of the


Report on the Damage to theCultural HeritageThe Great East Japan Earthquakeof March 11, 2011Toshikazu HanazatoMie University, Japan/ICOMOS Japan

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Damage Report of Japan ICOMOS.

Disaster of Tsunami (Minamisanriku-cho).

Ishinomaki St. John the Apostle Orthodox Church. Severely damaged but Survived by Tsunami.

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Partial Collapse of Stone Wall (SekinoichiSake Brewery).


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governmental projects of rehabilitation, such as reconstruction of cities/towns destroyed by the tsunami, delaysin starting, however, the restoration and rehabilitation stages have already come. In such social situation, somerestoration projects of the cultural heritages were starting or ready to start. However, in comparison with KobeEarthquake’s experience in 1995, it would take much longer time and cost to recover from the disaster. Japan ICO-MOS will hopefully prepare for publishing the following report on the restoration and rehabilitation of damaged cul-tural heritages.

For ISCARSAH Newsletter, damage to heritage structures is summarized as followings. In general, the maincause of the great disaster due to this major earthquake of magnitude of 9.0 was the powerful tsunami that hitthe coast area of East Japan along the Pacific Ocean. Although there existed not so many heritage structures inthe devastating tsunami area, some of traditional townscapes of fisherman’s villages were lost, moreover, dozensof architectural heritages were swept away and severely damaged. On the other hand, the earthquake groundmotions were characterized by the short predominant period and long duration, having caused serious damageto heritage structures with short natural period such as stone/brick masonry buildings and timber storehouseswith thick mud-walls. Most of the traditional timber buildings with rather longer natural period, however, werenot structurally affected by the strong ground motions exceeding 0.4G. Only a few vulnerable traditional tim-ber structures collapsed during the earthquake. Furthermore, liquefaction of sandy soils caused serious dam-age to traditional timber buildings.

Main Building of Historic Site, Yubikan: left, before Earthquake; right, after Earthquake.

Collapse of Stone Storehouse in Makabe. Siogama Shrine, Important Cultural Property Designated: No Damage.

he problem of the seismic pro-tection of the existing building

patrimony, has or not historic-artis-tic value, is essentially concernedwith knowledge, particularly as re-gards the actual level of hazard re-lated to the seismic threat in adefinite site. This knowledge more-over -and this is a distinctive fea-ture of the seismic problem- cannotbe based, except very particularcases, on tangible data, the seismicaction being occasional, transient,instant, unpredictable in the detailsbut with effects that from such de-tails depend significantly, and prac-tically not reproducible a-priori inits full individuality. It follows thatin the specific case the knowledgeis strongly based on the philosophy,and one must interpret the knowledge as the collection of all the objectiveelements that contribute to form the scenario in which the seismic eventoccurs and acts. With the awareness that none of such elements will havethe authority to determine any necessary conclusion, since the seismicevent has the power, at its actual occurrence, to disregard of, and even toclash with, every forecast of features that could have been correctly inferredfrom the logical system set up, so conflicting with prediction but not deny-ing the rationale that justifies the prediction itself. Anyway, earthquake prediction in conjunction with seismic risk prevention ac-tions is strongly debated, especially after recent earthquakes in Italy.One should first specify that prediction is generally qualified by two attributes:accuracy and reliability. As far as seismic occurrence is concerned, one shouldconsider that prevention is essentially realized through the improvement ofthe survival capacity of buildings, and the extension and strength of this ac-tion are conditioned by financial resources that are yearly made available.With elapsing time the residual risk of a destructive quake increases; andsince the rate of earthquakes in Italy is rather high, as resources and preven-tion advance, so the risk and the losses.On the other side, seismic hazard prediction usually conjugates good accu-racy with poor reliability, and/or vice versa. A typical statement with poor ac-curacy and high reliability is: “The probability that a destructive quake (sayM>5) strikes a given (wide) area is larger than Po (say Po > 0.1) in the next nyears (say n =10)”. In this case a good chance exists that improvement in thebuildings’ vulnerability will have some effect in the next n years, if the actionfor prevention is extended over the whole area involved by the prediction.


Earthquake prediction and seismic prevention

for architectural heritageAlessandro BarattaUniversità di Napoli

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Fig. 1 Estense Castle, Finale Emilia. Collapse of the donjon on the back.

Fig. 2 Finale Emilia. Clock tower before thequake of May, 20.

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Usually this purpose conflicts with available time. If n is small there is no timeto actuate overall reinforcement; if n is large there is time for seismic de-struction to occur in the meantime. On the other side the yearly financial amount that can be devoted to seismicrisk mitigation is limited. If protection is applied through sporadic localized ac-tions, it may sort no effect because earthquakes may strike other sites thathave remained unprotected. A typical statement with high accuracy and poor reliability is “The probabil-ity that a destructive quake (say M>5) strikes a given (small) area is largerthan Po (say Po > 0.01) in the next n years (say n =10)”. In this case the areawhere buildings should be improved is compatible with time and financialcosts, the operation can be sustained, but it is possible that such a lumpedarea will not be struck by earthquakes before 200 years or more. In otherwords, the prevention could well be so intense to ensure that no victims willbe counted in the next quake, but the costs are immediate and the benefitsmay be very far, and may be preceded by many other catastrophes in othersites. It is practically impossible, at the present state, to have both the attrib-

utes at a high level. In this sense, one should intend the common proposition that “earthquakes cannot be predicted”.This is in practice the situation all over the world. We know that earthquakes will occur, and perhaps, more or less wealso know when and where the next will occur. What is missing is a reliable coupling of time and space.The solution seems to push towards a large-area action, aiming at improving the capacity of buildings as much aspossible, compatibly with available times and resources, without prefixed objectives of protection, keeping the ac-tion into a sustainable domain. The result will be an improvement in the losses and in human lives saved, but any-way still many buildings and lives will be lost. The conclusion is that seismic losses can be mitigated but notannealed in a reasonable lapse of time. Architectural Heritage is inserted in this context, but in this case the scope is to keep buildings standing up, sincemost times they are not inhabited and human lives can be saved, in the limit, preventing people from entering intheir interior or neighbourhood. Earthquakes cannot be predicted in detail (space, time, perhaps intensity and soon). But let look at the Emilia-Romagna earthquake and at the damage that has been suffered by most monumen-tal buildings and assume that one with a magician's crystal ball some time ago would know that after 1000 daysan earthquake of Magnitude 5,9 with its actual epicentre would have shaken the region, thus predicting the time,the area, the local intensity of shaking, and everything else. After questioning some clever engineers and architects,they would probably closely describe the damage we see today. They should say that the quake couples a strong sussultatory component to horizontal acceleration. Stability of ma-sonry structures versus accidental (and seismic) loads is largely supported by their own weight, if this is large with re-spect to disturbance. In the presence of a vertical motion, the weight (but not the mass) of the building is timely reducedin some phases, while strong horizontal forces are acting. So large and extensive damage would be expected. Now theproblem is what to do in the 1000 days preceding the event. Looking at the Estense castle /Fig. 1) and at the ClockTower (Fig. 2) in Finale Emilia, and at the heavy damage they have suffered, one should ask what could be done to pre-vent such damage, considering that the situation is similar for other hundreds valuable objects in the region. Techni-cians know what to do and how to consolidate and retrofit buildings for seismic survival; many treatises and guidelinesare available and can be read, studied and applied. But a preventive action at a macro-scale is somewhat different thanoperating on a single building. Looking at the damage in the figures above, it is easy to understand that the towersshould have undergone some invasive works, possibly with the insertion of some tension-resistant prosthesis. All ofthis applied to all architectural heritage in the area. Potential costs, from the economical point of view, and potentiallosses on the cultural side, would have advised against this action. By contrast, it is possible that lighter works wouldhave significantly mitigated the earthquake's effects, today allowing cheap recovery and refurbishment. Technicallyspeaking, theory and practice are mature for operations; it is today possible to calculate seismic response of structuresand, may be, it is also possible to predict damage. What is still unknown is what should be done before earthquakesstrike down the monuments, and Research is claimed to outline an effective sustainable strategy for seismic preven-tion of the architectural heritage.24

Fig. 3 Finale Emilia. Clock tower after thequake of May, 29.

Documents

Iscarsah newsletter 1 Layout 1 - ICOMOS Open Archive ...openarchive.icomos.org/1582/1/Iscarsah_newsletter_1.pdf · Alessandro Baratta, Earthquake prediction and seismic prevention